The present relates to an input apparatus for operating a GUI (Graphical User Interface), a control apparatus for controlling the GUI in accordance with operational information thereof, a control system including those apparatuses, a control method, and a handheld apparatus.
Pointing devices, particularly a mouse and a touchpad, are used as controllers for GUIs widely used in PCs (Personal Computers). Not just as HIs (Human Interfaces) of PCs as in related art, the GUIs are now starting to be used as an interface for AV equipment and game devices used in living rooms etc. with, for example, televisions as image media. Various pointing devices that a user is capable of operating 3-dimensionally are proposed as controllers for the GUIs of this type (see, for example, Patent Document 1).
Patent Document 1 discloses an input apparatus including angular velocity gyroscopes of two axes, that is, two angular velocity sensors. Each angular velocity sensor is a vibration-type angular velocity sensor. For example, upon application of an angular velocity with respect to a vibrating body piezoelectrically vibrating at a resonance frequency, Coriolis force is generated in a direction orthogonal to a vibration direction of the vibrating body. The Coriolis force is in proportion to the angular velocity, so detection of the Coriolis force leads to detection of the angular velocity. The input apparatus of Patent Document 1 detects angular velocities about two orthogonal axes by the angular velocity sensors, generates, in accordance with the angular velocities, a signal as positional information of a cursor or the like displayed by a display means, and transmits it to a control apparatus.
Patent Document 2 discloses a pen-type input apparatus including three (triaxial) acceleration sensors and three (triaxial) angular velocity sensors (gyro). The pen-type input apparatus executes various operations based on signals obtained by the three acceleration sensors and the three angular velocity sensors, to thus calculate a positional angle of the pen-type input apparatus.
The acceleration sensors detect not only accelerations at a time a user operates the input apparatus, but also gravity accelerations. Because gravity that acts on the input apparatus and an inertial force of the input apparatus generated when the input apparatus is moved are of the same physical amount, it is impossible for the input apparatus to make a distinction therebetween. For example, when the user swiftly moves the input apparatus in a horizontal direction, a combined force of the inertial force and the gravity is misrecognized as being in a gravity direction (downward direction). The pen-type input apparatus of Patent Document 2 above detects triaxial angular velocities and accelerations in triaxial directions, that is, detects amounts in all 6 degrees of freedom, thus solving the problem on the inertial force and gravity as described above.
It should be noted that there are cases where a planar-operation-type mouse generally used nowadays includes an acceleration sensor (see, for example, Patent Document 3). An apparatus that uses this mouse outputs display data to a display section based on an acceleration of the mouse detected by the acceleration sensor.    Patent Document 1: Japanese Patent Application Laid-open No. 2001-56743 (paragraphs [0030] and [0031], FIG. 3)    Patent Document 2: Japanese Patent No. 3,748,483 (paragraphs [0033] and [0041], FIG. 1)    Patent Document 3: Japanese Utility Model Application Laid-open No. Sho 61-89940 (FIG. 1)
For using the 3-dimensional operation input apparatus described above as a planar-operation type like a generally-used mouse, the input apparatus needs to be provided with an optical sensor or the like for detecting that the input apparatus has been placed on a plane.
However, in a case where the optical sensor is provided, the number of components increases, thus requiring additional cost. Moreover, in a case where an optical sensor is provided in addition to an angular velocity sensor and the like for detecting a 3-dimensional movement of the input apparatus, a space for arranging the optical sensor becomes a problem, with the result that design of the input apparatus is restricted.
It is therefore desired to provide a 3-dimensional operation input apparatus, a control apparatus, a control system, a control method, and a handheld apparatus with which planar operations are possible without an increase in the number of components.